"Prices and margins have improved primarily because of a tightness in the U.S. sugar market," said Hal Mechler, Imperial's chief financial officer. That has allowed the company to raise prices 9 percent in the first quarter, which ended March 31.

For Houstonians, this is a mixed blessing.

Investors who load up on hometown companies may well have seen another quarter of good gains.

The Chronicle 150 rose 11.4 percent for the year, compared to the approximately 3.7 percent gains in the Dow industrials and the Standard & Poor's 500 indexes for the quarter. The local gain exceeded the American Stock Exchange Oil Index, which rose 8.5 percent.

The major indexes ended the quarter on a down note. The Dow industrials slipped 1.5 percent for the last week of the quarter while the S&P 500 was off 0.62 percent. The Houston 150 was up for the week, rising 1.5 percent.

Half of the top 10 performers in Houston are in a commodity business, like Imperial or Frontier Oil, which profited from the strong profit margins in the oil refining business, or they provided services for the energy business.

For consumers, there's a downside.

Rising commodity prices are a major factor behind the higher prices consumers are finding in their grocery stores, gas stations and utility bills.

"As a consumer you're going to pay more, but as an energy investor, you're going to be smiling as you put $3 gasoline in your tank," said David Pursell, a principal with Pickering Energy Partners.

While the U.S. Energy Information Administration is predicting gasoline will average $2.50 a gallon this summer, the unexpected could again move the market. Last year's hurricane season provided a graphic demonstration of the potential jolts from unexpected events.

"If there are any supply disruptions, then prices will go through the roof," said Richard Asplund, chief economist of the Commodity Research Bureau in Chicago. "It used to be that Saudi Arabia could come to the rescue, but now it doesn't have much excess production to do that."

Longer term this could turn into a major concern for investors as well because rising commodity prices may stoke inflation.

If global sugar prices meet U.S. prices, Americans will find themselves paying more to sweeten their iced teas this summer and their apple pies this fall and worrying about inflation.

Federal Reserve policymakers are already contemplating the troubles commodities could pose for the economy.

In a post-meeting statement Tuesday, the committee that manages interest rates cited "elevated prices of energy and other commodities" as inflation risks. Previously, the committee only mentioned energy as a worry.

And when the Federal Reserve Board is concerned about inflation, it resorts to higher interest rates to cool the economy, which is not a comforting prospect for investors.